NMR is used to study biological macromolecules, with emphasis on kinetics and on instrumentation for protein proton spectroscopy in 100% H2O. Transaminases are studied primarily through studies of isotope exchange of substrate. Hemoglobin ligation kinetics will be measured by various pulsed techniques. Kinetics of proton exchange with solvent are being studied for tryptophan indole N-protons and will be extended to other molecules including tRNA's. Relaxation times and transfer of saturation are being observed for mammalian and yeast cytochromes-c.